Discovery of Random Delay Distribution Based on Complex WSNs Clock Synchronization

With the rapid development, Wireless Sensor Networks (WSNs) technology has been widely applied in many fields, such as military intelligence detection, medical condition detection, urban facility construction and smart home, etc. Clock synchronization is one of the key technologies in WSNs, precise node time synchronization is critical for many networked control applications in WSNs. Once the clock of sensor nodes loses synchronization, the information collected by nodes will lose timeliness and value for users. Therefore, the key technology of clock synchronization plays an important role in WSNs. The main purpose of clock synchronization is to control the interval time that between sending and receiving timestamps of wireless sensor nodes within acceptable clock synchronization accuracy. However, because there are many kinds of link delays in the process of information transmission, the transmission time is prolonged and the time precision is reduced. Therefore, it is necessary to study the exact causes and effects of these errors. In ZigBee wireless sensor network, through theoretical model and data experimental analysis, we got the result that the random delay distributions of the uplink and downlink obey normal distribution when the sensor nodes exchange some information.